Teikoku USA | Chempump
Instruction Manual HE-12270 (1219)
10
starved for liquid during operation. NPSH problems are a result of
improper suction systems.
The suction pipe should be one or two sizes larger than pump
suction port, depending on piping length. Use the largest pipe
size practical on suction piping and keep piping short and free
from elbows, tees or other sources of pressure drop.
If elbows, tees or valves must be used, locate them from 5 to
10 pipe diameters upstream from the pump suction inlet. When
reducing to pump suction port diameter, use eccentric reducers
with flat side on top to avoid air pockets.
A vent line back to the suction vessel is required in the discharge
pipe. The connection for the vent line in the discharge pipe must
be between the pump discharge flange and the first block valve
and/or check valve. Install a block valve in the vent line. When a
solenoid valve is used for the start vent, program the solenoid
valve to be open when the pump is off and closed when the
pump is on. Refer to
Appx. D
piping layout for the Type-F (Plan
1-SD) pressurized circulation ALP multi-stage pump.
If discharge pipe length is normal, pipe diameter can be the same
size as the pump discharge port diameter. If discharge piping is
of considerable length, use one or two size larger diameter pipe.
If the pump is to discharge into a closed system, an elevated tank
or if there are multiple pumps connected together, place a check
valve in the discharge line close to the pump.
NOTE:
Install properly sized pressure gauges in suction and dis-
charge lines between the pump and the first block and/or check
valve so that operation of the pump and system can be easily
observed. Should cavitation, vapor lock, or unstable operation oc-
cur, widely fluctuating discharge pressures will be observed. Such
gauges provide a positive means of determining actual system
conditions and can be used to great advantage in evaluating sys-
tem problems.
2.3 Electrical and Instrumentation
2.3.1 TRG Bearing Wear Monitor
The TRG is an electrical meter that continuously monitors the con-
dition of the bearings. The TRG is mounted on the electrical junc-
tion box as standard.
The TRG meter operates on the principle of induced voltage.
There are two TRG coils located inside the stator 180° apart. A
magnetic field is created in the stator by current flowing through
the stator windings. In addition, a magnetic field is created by
induced currents in the rotor. When the rotor is perfectly centered
in the stator, the two magnetic fields are essentially balanced.
When bearing wear occurs and the gap between the rotor and
stator decreases, an imbalance in the magnetic fields causes a dif-
ferential induced voltage in the TRG coils. This differential voltage
is indicated on the TRG voltmeter.
The initial display of the TRG meter is adjusted in the Teikoku
factory, but each meter will show subtle differences. To check
bearing wear using the TRG meter, use the color change (Green,
Yellow, Red) as a reference. If the increase of TRG readings is 0.3
or more, stop the pump and check bearings.
The Teikoku Rotary Guardian (TRG) signal is affected by motor
load. Changes in operating frequency or hydraulic load may in-
crease or decrease signal.
Keeping records of the TRG meter reading in conjunction with
motor amp readings will provide a good indication of when the
pump will require maintenance.
Figure 2-1. Teikoku TRG Bearing Wear Monitor
Table 2-1. Conditions Indicated on the TRG Meter
The TRG meter has a colored scale which is divided into three zones: Green (0 to 0.5), Yellow (0.5 to 0.75), Red (0.75 to 1)
AT TRIAL OPERATION
DURING OPERATION
Indication
Condition
Solution
Indication
Diagnosis
User Actions
Full scale or 1-Volt
incorrect wiring
change power cable
connection
Green
Good
No action
Yellow to Red
phase failure
check connection of
cables
Yellow or voltage increase of
> 0.3 V from initial indication
Bearings worn to
caution level
Plan routine
maintenance
Green
normal
connection is correct
Red or voltage increased of
> 0.5 V from initial indication
Immediate
maintenance required
Shutdown immediately
and replace worn parts
Hazard!
Do not operate if TRG meter condition is RED.
